This is my very first try with extension tubes combined with a 24-105mm F4 Canon lens. The lens is extended to 105mm and I used a 36mm extension tube for the macro effect. I must say I am surprised how well these tubes work. Although I would like it if my lens were an F 2.8 instead of an F4. Notice the little insect on this clover flower. Yes, this is a clover flower which is smaller in diameter than a dime.